This research proposes to explore mechanisms by which virus infections provoke asthma attacks, some host factors which may alter the immune response and will attempt to devise simple ways to interrupt viral transmission. The viral mechanisms are analysed in two ways, using granulocyte receptors as an indicator of beta adrenergic response and in vitro smooth muscle preparations obtained from autopsy specimens. Host factors are analysed by characterizing the isotype responses in serum and secretions and studying mechanisms of IgE control in biosynthesis experiments.